A museum devoted to the pop superstars opening in Stockholm on Tuesday will celebrate the band’s long list of hits. But it will also show off paraphernalia, including the helicopter featured on the cover of its “Arrival” album, a star-shaped guitar and dozens of glitzy costumes the Swedish band wore at the height of its 1970s fame.

Some gear is definitely not on show. With a smirk on his face, band member Bjorn Ulvaeus says certain items are “mysteriously … forever lost,” conceding only that among them are “embarrassing” tight costumes he wore when he was “slightly overweight.” He declined to say more on the matter.

Some 40 sets of the trademark shiny flares, platform boots and knitted hats are on display in the museum. But visitors can also see digital images of what they would look like in costumes, record music videos and sing such hits as “Dancing Queen” and “Mamma Mia” on a stage next to hologram images of the band members. A telephone also has been placed in a corner and ABBA members have promised to “Ring, Ring” and speak to visitors occasionally.

But the museum also shows a less glamorous, more everyday side of the history of a band that has sold 400 million records and consistently topped the charts in the decade after winning the 1974 Eurovision Song Contest with “Waterloo.” The band — made up of Ulvaeus, Anni-Frid Lyngstad, Benny Andersson and Agnetha Faltskog — started out as two married couples, and continued performing after their divorces, before eventually drifting apart in the early 1980s.

The collection includes models of the band’s kitchen, a cottage where they used to compose their songs and the small, rustic park venues Bjorn and Benny played when they first met in the 1960s. Visitors can listen to the band members’ recollections and one section is dedicated to the breakup and the story of the divorces.

“It (touches) on those things as well because we think they are important in telling the story,” Ulveaus said.

The museum also includes a Swedish Music Hall of Fame, detailing other Swedish artists.

It was a long time coming, eagerly anticipated by fans and visitors to the Swedish capital. Ulvaeus said they needed the time to reflect on their careers. “You need some distance, you need perspective to be able to tell a story like that and I guess you can say that we have perspective now, 30 years on,” he told reporters.

Outside the newly built wooden museum scores of international ABBA fans gathered Monday, singing the band’s songs and hoping to get a glimpse of their idols arriving for a gala dinner. All were expected except Faltskog, who is currently promoting her comeback album “A” in Britain.

Nikita Stolyarov, a 21-year-old student from Russia said he got a glimpse of Lyngstad on Sunday when she came by for an early view of the museum.